Productivity of maize-bean intercropping in a semi-arid region of South Africa

Food shortage is known to have been caused by overpopulation, natural disasters and poor food distribution. In areas facing food insecurity such as Africa, peasants or small-scale farmers have practised intercropping since old times. In this study, an investigation was carried out to determine whether intercropping increased production for small-scale farming in a semi-arid region (Free State, South Africa). Crop productivity of maize and bean intercropping systems was evaluated in terms of yield and growth. The effect of radiation and water utilisation by these systems was measured to determine their productivity. Field trials were carried out during three summer crop growing seasons (plant densities, row orientation and sowing date trials. In all growing seasons, rainfall was below normal, and air temperatures were normal. The total land equivalent ratios for yield and growth ranged between 1.06 to 1.58 and 1.38 to 1.86 respectively, showing yield and growth advantage of intercropping. Concerning radiation and water use, the intercropping of maize and beans had both radiation and water use efficiencies (RUE and WUE, respectively) as high as maize sole cropping, and intercropping RUE and WUE were greater than bean sole cropping. From these results it has been concluded that maize bean intercropping can be recommended to small-scale farmers in this semi-arid region.